Quote: "The problem could be in the cab-tire. At first glance it souncs like I know what I'm talking about, except I have no clue what cab-tire is."
LOL I would expect nothing less from somebody who chooses "homer" as a nick.
Everybody around here refers to "flexible cable having a heavy rubber or neoprene outer sheathing" as cab-tire, don't ask me why.
As to the generator problem,Sparkyinak nailed it...no neutral bonding at the generator. I was thinking that the problem would be more along the lines of what frenchy was getting at, but at least it was a simple fix. The repair place called the site super yesterday and told him they had inspected the gen-set and it was working properly, and they would return it. When I got to the site this morning the generator was back. I opened the cover on the termination cabinet to re-attach the cab-tire and the first thing I noticed was a bonding jumper going from the neutral bus to the ground lug. I know this jumper was not there two days ago because I looked for one. I mistakenly assumed that the bonding had been done inside the unit somewhere.
I'm really surprised how much of a difference can be made by removing the neutral bond, I never would have guessed it would be this dramatic.
This generator has been on-site for about 6 weeks in this condition, I'm surprised nothing bad has happened.
Thanks for the responses!
p.s. the gen-set was feeding a single phase panel so C phase was not being used